By xe2x80x9cFreight containersxe2x80x9d we mean ISO standard freight transport containers but clearly the invention can be adapted to suit any standard container size. These are routinely transported by road, rail or ocean freight. The purpose of the container is to transport and discharge any bulk solid irrespective of the bulk density of the material or its flow characteristics.
The apparatus aspect of the invention provides a self-discharging freight container for bulk solids comprising:
a static frame capable of supporting the container and contents;
a container hinged to the frame along a tilting axis at or near the top of the frame;
the container having a hinged floor which tilts to release the contents when the container is tilted toward a discharge position;
wherein,
the container has a pair of mutually spaced, triangular braces adjacent the hinge axis; and
a thrust point along each brace and a reaction point on an adjacent part of the static frame between which points a discharging force is exertable.
Preferably the braces extend into the container interior. They may be located symmetrically along the length of the container and mutually separated by half the length of the container. The force may be exerted by rams each of which works in a pocket provided in the container interior. The brace may be reinforced by a strut extending from the hinge axis and the thrust point is at the intersection of the brace and the strut.
A flow control surface is located at each end of the floor externally of the container to direct exit flow. The flow control surface may be a plate extending uprightly from the floor, the length of the plate being equal to the floor width. The flow control surface may contact a seal surface on the adjacent end wall of the container. This may be a flexible seal strip which lines the junction between the container walls and the floor in order to arrest particles. The floor itself may be faced with a hard wearing polymer suitable for bulk solids handling with a useful coefficient of friction. A floor vibrator such as an eccentric weight device may assist solids flow.
If multiple rams are used, say every 2.5-3 m along the length of the container, then rams used in the construction of agricultural machinery may be used. Hydraulic tilting of the container is convenient but in an alternative version the container has a lifting point on the side of the container opposite to the hinge axis so the container may tilted by external means. This permits discharge by an overhead crane. In this instance the rams remain connected and damp the initial discharge movement which would otherwise be too sudden.